The aircraft was designed in response to a Polish Air Force requirement of 1946 for a trainer to replace the Soviet UT-2, which was obsolete. The new aircraft was designed in 1947 in the LWD - the first Polish post-war construction bureau. The chief designer was Tadeusz Sołtyk. A prototype named the LWD Junak, later the Junak 1, was flown on February 22, 1948. The entire design was Polish, except for the engine, which was a license-built Soviet radial, the Shvetsov M-11D. After tests, an improved variant, the Junak 2 was flown on July 12, 1949. Notable changes from the Junak 1 included the cockpit being moved forward, the fin being increased in area, a more powerful M-11FR engine was fitted and the massive landing gear covers were deleted. The plane's handling improved. The LWD team disbanded in 1950 and Junak 2 development was continued by the CSS workshops in Warsaw. After further improvements the prototype was designated the Junak-2bis, but finally entered production in 1951 as the Junak-2. Tadeusz Sołtyk was given a State Award in 1952 for the design. From 1951 to 1954, 105 Junak 2s were produced in the WSK-Okęcie in Warsaw. Tadeusz Sołtyk, then working in the Aviation Institute in Warsaw, proposed a Junak development with a bubble canopy, retractable landing gear and other improvements, designated the TS-7 Chwat, but it was not ordered by the authorities and remained on the drawing board. Instead, when the Polish Air Force was equipped with its first jet fighters,, there appeared to be a need for a trainer with a tricycle landing gear. Sołtyk designed a modified Junak with a fixed tricycle landing gear and other minor improvements. This plane entered production as the TS-9 Junak 3, after having first flown on August 7, 1953. The new plane was heavier, its maximum speed dropped from 223 km/h to 205 km/h. Between 1953 and 1956, 146 Junak 3s were produced in WSK Warszawa-Okęcie. Along with the Junak 1, the LWD developed a civilian trainer and aerobatics variant, the LWD Zuch. Only 5 Zuch 2s were built in 1950, powered by a 116 hp Bramo Sh 14radial engine. The Junak was the first aircraft mass-produced in Poland after World War II, the Polish aviation industry having been annihilated. Despite not being particularly modern, it was a stable and easy-to-handle aircraft, with an uncomfortable cockpit being one of its few flaws. On the other hand, it was considered a difficult aircraft to learn to fly, because a student in a rear cockpit had worse view. All models of Junak are generally referred to as LWD Junak or WSK Junak, while the designation TS-9 is not commonly used. The designation IL Junak 3 sometimes appears in books.
Design
The aircraft was of mixed construction and conventional in layout. The fuselage consisted of a steel frame, covered with canvas, in front with metal sheet. It had two-spar wings of wooden construction and a trapezoidal shape; they were covered with canvas and plywood and were fitted with split flaps. It had a two-seat cabin with a common closed canopy. Landing gear was conventional or tricycle and fixed. A 5-cylinder M-11FR radial engine gave 119 kW of maximum power and 104 kW normal power. The cylinders have individual cowls, which were often removed. The aircraft was fitted with a two-blade fixed pitch wooden propeller. It carried 80 liters or 100 liters of fuel. The plane had no armament. The Junak 3 was fitted with a radio.
Operational history
Junak 2s were used in the Polish Air Force as a basic trainer from 1952. When their replacement, with Junak 3s, started in 1954–55, the Junak 2s were withdrawn from the Air Force and handed over to civilian flying clubs. Junak 3s were used in Polish military aviation from 1954 until 1961, when they were finally replaced with the TS-8 Bies. Starting from 1956, they were handed over to flying clubs as well. In civilian aviation, 71 Junak 2s and 93 Junak 3s were distributed among aero clubs, who suffered a shortage of suitable aircraft after the war. They were used for pilot training and glider towing throughout the 1960s. The last Junak 2s and Junak 3s were retired in 1972. In 1963 a group of 12 African pilot trainees from Algeria, Togo and Angola were taught to fly at Krosno, Poland, and they flew Junak 3.
